Machine for welding and forging metals



Oct. 29, 1940. E GASPAR MACHINE FOR WELDING AND FORGING METALS FiledJune 30, 1939 3 Sheets-Sheet l LM, M 9M@ )hing Oct. 29, 1940.

E. GASPAR MACHINE FOR WELDING AND FORGING METALS Filed June 30, 1939 3Sheets-Sheet 2 @N w@ Nw Q@ @RW H..WH.........| M H 3 Sheets-Sheet 3 R@mvNw@ @mU/// Oct. 29, 1940. E GASPAR MACHINE Foa WELDING AND FORGINGMETALS Filed June 30, 1939 Patented oct. 29, 1940 MACHINE FOR WELDINGAND FOBGING LIETALS Emeric Gaspar, London, England, assigner to OmesLimited, Barnes,

British company London, England, a

Application June 30, 1939, Serial No. 282,245 In Great Britain April 13,1938 2 Claims.

This application was flled in Great Britain on April 13, 1938. Thisinvention comprises improvements in or relating to machines for electricworking of metals, and the invention is hereinafter describedl asembodied in an electric forging machine which can also be employed forelectric welding operations.

In electric iiash or butt welding the welding operation proceeds in twostages, namely the first stage in which, when the pieces to be unitedare brought together, the current is employed in heating the workpiecesat the joint and in melting the metal on the surface where it is to beunited, and the second stage in which the pieces are forced together toeffect their union. In the first stage a gradual approach of the piecesto be united, with a light pressure, is required, whereas in the secondstage a relatively rapid movement under a heavy pressure is called for.These two movements are usually effected by a cam device, the vcamhaving a slow motion portion over the heating stage and a change in itscontour at an appropriate point to bring about the extra motion requiredfor union.

In electric forging machines the workpieces are held so that they extendbetween two electrodes and are heated by a current passing through themfrom one electrode to the other, the workpiece being either pressedthrough one electrode towards the other so as to cause a'bulge on itsend or at an intermediate point of its length, or, again, the workpiecesmay be subjected to tension so as ,to cause them to be thinned out to aneck, or actually broken, leading to the production of two pointed lworkpieces.

In electric welding, as in electric forging, a step-down transformer isordinarily adopted for supplying current to the electrodes, but thevoltage required in the case of electric welding is higher than in thecase of electric forging.

It is an object of the present invention to provide a machine which iscapable of bc*h welding and forging operations as may be desired, and inthe preferred form of the machine hereinafter described both upsettingand stretching operations can be conducted as well as welding, but it isto be understood that it is not essential, in

` accordance with the invention, that every kind of electric forgingoperation as well as welding should be capable of being conducted in themachine.

According to one feature of the invention a combined butt Welding andforging machine comprises in combination a bed, two vice electrodes,

two feed devices one for preliminary moving one vice electrode and theother a heavy-pressure feeder provided with a ram to engage the ends ofworkpieces to force them through the second electrode for upsetting orWelding operations and a regulatable transformer connected to theelectrodes, the voltage variation of which adequate to ,enable it tosuit both welding and forging operations.

The first said vice electrode which is connected to the preliminaryfeed-device may be adapted to receive an anvil electrode forend-upsetting when desired.

A trip or switch may be provided operated by the preliminary feed-deviceor a part moving therewith, the said trip or switch serving to coni trolthe heavy-pressure feeder so as to bring it into action automaticallyafter a predetermined degree of movement of the preliminary feeddevice.

Preferably the heavy-pressure feeder consists of a hydraulic cylinderand ram.

The heavy-pressure feeder may be provided with an adjustable stop forautomatically ter- -minating its feed movement in any desired position.

The heavy-pressure feeder may, moreover, be provided with means toconnect it to the said second electrode when desired so as to cause the.electrode to move along the bed and be made reversible, that is to saycapable of exerting feeding force in both directions, so thattension-forging operations can be conducted if desired. Preferably ithasan adjustable reversing device for automatically reversing its feedmovement towardsthe vice electrodes at a position correspending to theposition of adjustment of the reversing device.

One example of a machine constructed in accordance with the inventionwill now be described with reference to the accompanying drawings, inwhich:

Figure 1 is a side elevation of the machine, certain parts being shownas broken away or in section;

Figure 21s a plan of the same;

Figure 3 is an enlarged view of the electrodes showing an anvil locatedin one of them for. upsetting purposes, and

Figure 4 is a diagrammatic representation of the working parts and ofthe hydraulic and electrical connections thereof.

The machine comprises a horizontal bed plate H provided withlongitudinal guideways I2 and arranged above a frame consisting ofvertical members I3 and a horizontal base I4. 'I'he frame contains anelectrical step-down transformer which is shown dlagrammatically at l5in Figure 4 of the drawings, together with appropriate control gear.including means for the supply of oil under pressure for operating thehydraulically controlled portions oi the apparatus.

Upon the bed plate i i there are disposed two slidable work-holdingelectrodes i9, il in the form of vices. The vices lo, il are in theiressentials similar to one another. They each comprise a base i@ mountedso as to slide on the guideways i2. The base of the vice il is insulatedfrom the machine bed plate. The base i8 is shaped to support a lowervice Jaw i@ which is interchangeable and is adapted to iit closely upona workpiece 2li. Each oi the bases i8 is connected to one oi theterminals oi the transformer i5 by iexlhle leads and the bases and thevice jaws are made of a material which is a good conductor ofelectricity, such as bronze, so as to con- Vey current to the workpieces2li eciently. The vice frame in each case rises behind the vice jaws toa height above the workpiece where it carries a hydraulic cylinder 2iarranged with its axis vertically above the lower vice jaw i9 and havinga ram 32 which carries a movable upper vicejaw holder 23 in which issupported an upper vice jaw 2i.

The two vices it, il are arranged with their vice jaws in line with oneanother considered in a direction parallel to the guideways i2 of thebed plate, and the vice jaws it, 2d are made hollow and provided withcooling water connections 25, 2% (Figure 2).

The vice il is connected by a pair of struts 2l to a sliding head 25which runs on the guideways l2 and is secured to a screwed feed rod 29.The struts 2 are insulated from the 'case I9 of the vice li. The head2t! also carries an abutment 3@ to engage the end of the workpiece Eilheld in the vice il; the abutment 3i? is insulated from the head 28. Inthis way the vice i8 and the workpiece held therein is eil'ectivelyinsulated from electrical connection with the other vice except throughvthe portion of the workpiece which projects towards the vothervice orpasses through it.

The screwed rod 29 extends parallel tothe guideways i2 oi the bed plateand enters a nut 3i which is held from longitudinal movement by beingmounted ior rotation in a cross bracket 32 which spans the guideways i2near their end. 'The nut 3i has worm-wheel teeth cut around its exteriorand the bracket 32 also carries bearings for a worm 33 which meshes withthe wormwheel teeth and forms part ci a cross shaft 3&3. The shaft 3dcarries a sprocket 35 connected by achain 3E to a second sprocket 3lmountedon the spindle of a hand wheel 38 (see Figure 2); thus the viceil can be moved along the guideways i2 by hand in either direction andthis mechanism constitutes a preliminary feed-device connected to thevice l?.

The other vice i6 is shown in Figure 2 as connected by struts 40 toanother sliding head M mounted on the guideways l2 and rigidly connectedto a ram 42 of a hydraulic feed cylinder 43, secured in the opposite endof the'bed l I from the work-gear 32. The hydraulic cylinder 53 isdouble acting so that it can force the head 4i to move in eitherdirection and is provided with hydraulic supply pipes M, 45 connected toits two ends. An adjustable stop rod l lies in line with the centre partof the lhead 4i and limits movement oi' retraction of the ram 42. TWO

aciaeve screwed stop rods ll'lare provided which enter -screwed holes inthe sides of the cylinder 43 and pass freely through the head All.Beyond the head the stop rods are provided with'sprockets de connectedby a chain i9. One oi the stop rods il has a handle 5t by which it canbe rotated. The stop rods l can be adjusted by their rotation so thatthey project to any desired distance from the end of the cylinder 53 andtheir heads 5i which lie beyond the sliding head tli serve to limitoutward movement of the ram d2. In the end ofthe ram #l2 there isscrewed an abutment-bar 52 the end of which serves to engage the end ofthe work-pieces 2li when these are inserted in the vice le. In order tosuit var ious sizes of workpiece a number of abutmentbars 52 ofdierentlengths are provided. When the bars are long they may besupported at an intermediate point oi their length by a cross bracket 53mounted on the bed plate and provided with a guidehole 'through whichthe bars 52 can slide.

It should be understood that the bars lli which connect the head di withthe vice iB are ar ranged to he readily removable when desired, as theyare not required for all the operations of the machine. To this end theymay be secured in place by set-screws t.

The head 23 which is connected to the handmoved vice il carries astriker Si) the purpose of which is to operate a limit switch. To thisend a sliding bar 6i is mounted on the bed plete ii parallel to theguideways l2, being supported by bearings 2. A spring 3 tends to movethe bar 5i to the right as viewed in the iigure and an adjustable collarSil can be set in any desired position along the bar ti, the collarbeing in the path of the striker te. Thus the bar 5i will be movedendwse when the striker engages the coi lar. The end of the bar Si isbent downwards at 55 and passes throught a slot in the bed plate intoengagement with a linut switch Hi8 (shown in Figure 4), thecontacts ofwhich are closed when the bar is moved by the striker.

At the other end of the machine the head di is provided with a strikerlli which works above two sliding bars il, l2 which are mounted in asimi- -lar way to 'the bar ai just described and are provided with stopcollars 73, 'i4 for engagement with Ithe striker. IThe bar 7l isconstrained by a spring it to move normally toward the end of themachine bed and is :bent down at its other end .through a slot l5 to.the inside of the machine where it is connected to a sliding interlockbar il. The other bar l has a spring i8 tending yto move it away fromthe end of the machine bed and is bent down through a slot 19 .to theinterior of the machine where it is connected Ito a second slidinginterlock Ibar 3U'. The interlock bars 1l, 8S serve to aord automatic:zo-operation with two hand control levers 8i, 82 which determine theoperation of the hydraulic control cylinder 43 (of the heavy-pressurefeeder) and El (of the vice cylinders i5, il).

Referring .to Figure 3, lthis shows the vices I6, il in .the positionwhich they occupy when. the machine is set up for upsetting a head onthe end of a workpiece 20. I'he vice IG contains vice jaws i9, 25 asalready described but in the vice ll there is inserted instead of thevice jaws an anvil carrier 85. The anvil carrier 85 has a head S6 on theside which faces toward the vice i6 and a clamping plate 9? which issecured .to the carrier 85 fby screws 88. 'Ihe clamping "plate 8l' is onthe opposite side of the vice from the head 8B and lil the'screws 88serve .to draw the head 88 firmly against the vice body. A wedge device88 is driven in .beneath the cylinder 2| so as to keep the ram 22 in itslowermost position and help in clamping the anvil carrier 85 inposition, In the anvil carrier there is secured an anvil 80 which isdrawn home against a conical seat 9| by means of an axial bolt 32. Awater cooling chamber 83 islprovided in 'the anvil and is supplied withcooling water through a pipe 84 passing through the centre of the bolt92. The cooling water is withdrawn through a pipe 95 from a lateralexhaust chamber 86 located in the -anvil carrier 85 closer behind theseat 8| and communicating with the cooling chamber 83 by means of atransverse ybore in the anvil 30, which bore is not shown in thedrawing, as it falls in a dierent plane from the section shown.

Referring rto Figure 4, in this ligure the working parts are letteredsimilarly to the corresponding parts in Figures 1 to 3 vbut in ordertoindicate the interconnection of the various parts they have lin somecases been displaced from `'their correct relative positions so thattheymay all appear clearly in the diagram. The transformer I is shown asprovided with a secondary winding |00 which is connected to the bases |8of the vice electrodes.|8, |1. The transformer has a primary winding |0|provided with a number of tappings connected .to regulator contacts |02and by selecting the position of a selector` arm |03 upon the contactsvarious secondary voltages become available on the transformer. Therange of voltage regulation is sufficient to ensure that a high enoughvoltage is available for welding when the machine is required for .thispurpose and also a low enough voltage for forging operations when theseare to be carried out. For thi-s purpose the voltage range on thesecondary side of the transformer should extend :from somewhat belowfour volts to above eight volts. Any other desired means of regulatingthe transformer voltage can be adopted providing a suitable range ofregulation is thereby provided.

. The supply means for the transformer current 'which hydraulic pressureis kept up by a pump ||1 which supplies the hydraulic elements of themachine. maintained the switch ||5 is kept closed and the clapper switchwill therefore be energised, subject to the control of the Vpush button||2. If, however, for any reason the 'hydraulic pressure should fail theswitch ||5 opens andthe electric supply is automatically put out ofoperation. This prevents burnt workpieces in the event of hydraulicfailure.

A hydraulic control valve Ibox is provided f which is supplied withhydraulic pressure from the pump ||1 by means of a pipe |2|. The valvebox is connected Iby an exhaust pipe |22 to a sump |23 from which Ithepump ||1 draws its supply. The pipes 44, 45 of the hydraulic cylinder 43are connected to the valve box |20 and the box contains valves under thecontrol of the As long as Ithe hydraulic pressure is' Ilever 8| suchthat when the lever is raised fthe pipe 44 from the front end of thecylinder will be connected to the pressure supply and the pipe 45 tothek back end of .the cylinder to exhaust. Thus;y .the ram 42 will lberetracted. When the lever 8| is depressed the connections in the valvelbox |20 reverse an-d the ram 42 will .be advanced. In a similar way thelever 82 control-s pipes |30, |8| leading to t-he control cylinders 2|of the vice electrodes I6, I1. The pipe conveys pressure to open thevices and the lpipe |3| conveys pressure to close the vices. The valvesin lthe lbox |20 which are under the control of the lever 82 are such.that when ,fthe lever is raised the vices are opened and when it isdepressed t-he vices are closed.

Above the lever 82 for closing the vices I8, |1 there is a sliding latchwhich is formed on the end of the sliding rod 80 operated by the stop 14hereinbefore described. Owing to `the spring 18, should the lever 82 bedepressedthe latch |35 moves to the right and comes over the lever 82,holding it down against the action cfa return spring |36. If the viceelectrodes are closed therefore they will normally remain closed owingto the latch |35 but they will be released automatically upon .thestriker 10 engaging the stop 14 when the ram 42 reaches its retractedposition. A

Similarly the rod 1| which carries the stop 13 is connected to a latch|31 and if the lever 8| is depressed so as to cause the ram 42 toadvance, the latch |31 is moved to the left, as viewed in Figure 4, bythe action of the spring 15 and the latch |31 holds the lever 8| downagainst the action of a return spring |38. Upon the ram 42 reaching theposition at which the striker 10 engages the stop 13 the rod |31 will bereleased and the lever 8| will rise, reversing the movement of the ram.The stop 13 therefore determines the limit of forward movement of theram 42 and secures its automatic return. In addition to being releasedby the action of stop 13, the latch |31 can be released by means of abellcrank lever |39, one arm of which works between pins on the stem ofthe latch |31 and the other arm of which carries a solenoid core workingin a solenoid coil |4|. The coil |4| is capable of being energised fromthe supply terminal |09 through contacts |42, |43 which are closed bythe push button ||2 when it is depressed to break the circuit of thecontacter |01. Consequently operation of the push button I2 will notonly cut off the electric current but lead to a return movement of theram 42 should this be advancing at the time when the push button isoperated.

The lever 8| is also provided with a solenoid core |45 having a. coil|46 so that in addition to being depressed by hand it can be pulled downautomatically in certain circumstances. The con` nection of the coil |46Aproceeds from the supply terminal |08 through the coil and thencethrough a limit switch |41 to the limit switch contacts |48 which areclosed by engagement of the stop 64 by the striker 60 on the head 28 ofthe hand-operated preliminary feed mechanism. The limit switch |41 issuch that the circuit is completed when the parts are in the positionshown in the drawing with the latch |31 moved to the right to allow thelever 8| to occupy its upper position, in which the ram 42 is movedrearwardly. Should the latch |31 be moved to the left, the circuit isbroken at the switch |41. I

The lever 8 I, moreover, carries an interlock arm, |50 which is mountedon an upstanding pivot on the lever 8i and can be swung by means of ahandle so that it overlies the lever 82. When in this positiondepression of the lever 3| will cause simultaneous depression of thelever 82 and thus the ram d2 will be advanced and the vices i6, l1simultaneouslyclosed. If the ram E58 is swung out of the Way, however,the depression of the lever 82 to close the vices becomes independent ofdepression of the lever 8| to advance the ram.

In the operation of this machine, if electric welding is to be effectedthe transformer i5 is adjusted to give a suitable welding voltage andtwo workpieces 28 to be welded together are held in the vices 8, l1 bydepression of the hand lever 82, the ends of the workpieces which areto' be welded being slightly separated and the other ends engagingrespectively the abutments 38 and 52, A preliminary feed movement iscarried out by means of the handwheel 38 which advances the vice I1 andwith it its workpiece until the two workpieces touch one another. Theusual burning off operation is then eifected by keeping the vicesappropriately adjusted until the ends of the workpieces have reached asuitable heat. This involves a gradual feeding of the vice |1 toward thevice i6, and, if the stop 64 is suitably adjusted beforehand, when theburning ofi operation is complete and the parts are ready to be welded,the limit switch contacts |48 will be closed, thus operating thesolenoid |46 and causing the rani 42 of the heavy-pressure feedermechanism to advance and push the workpiece 20 through the jaws of thevice i5 against the workpiece which is held in the vice |1 with a heavypressure, thus completing the weld. As soon as the operator sees thatthe weld is complete, he depresses the push button |2 thus cutting ofi'the electric current and, through the contacts |42, |43, actuating thesolenoid |4| which releases the latch |31- and permits lever 8| to rise,returning the ram 42 to its initial position. During these operationsthe lever 82 remains depressed, but can be released by the operatormoving the bar 12 in order to free the latch |35. Any

numberof welding operations on similar pieces can follow one anotherwith great rapidity owing to the semi-automatic action of the parts.

For upsetting a head on the end of a workpiece the anvil 98 is insertedin the vice |1 and the larm 858 is brought into-position above the lever82. Upon insertion of a. workpiece in the vice i6 and depression of thelever 3| by the operator, the vice I8 will be automatically closed andthe ram 42 advanced simultaneously. As soon as forging A temperature. isreached, upsetting will commence against the anvil 90. If a large headis required the operator can retract the anvil by working the handle 38during the upsetting operation. As soon as the striker 10 engages thestop'13, which is suitably set beforehand, the lever 8| would be freedby movement of the latch |31 and will rise, thus reversing the movementof the ram. The operator will simultaneously cut oi the current by theaid of the push button H2. If desired he can employ the push button ||2for releasing the latch E31 also, instead of using the stop 13. As soonas the ram 42 reaches its fully retracted position, the striker 18 willengage the stop 14 and release the lever 82, thus opening the vices andpermitting the workpiece to be removed. Any number of similar upsetheads can be produced in rapid succession in this manner.

If a series of upsets on workpieces are required which are to beproduced at an intermediate pointin the length of the workpieces, thisis done by using the same vice jaws as are used for welding, so that theappropriate part of the workpiece which is to be upset lies between thevice jaws, andA then proceeding in the same way as for upsetting a headon the end-of a workpiece.

If it is desired to effect a drawing operation on a workpiece, theworkpiece is mounted between the vice jaws in the same way as forupsetting a head at an intermediate point along its length and the bars48 which unite the vice i6 to the head M are p'ut in place. The lever 8|is depressed before the vice jaws of the vices i8, |1 are closed so asto ensure that the head 4| is in its fully extended position. The arm|50 is, during this operation, swung out of the way so that the vicejaws can be closed separately when the ram 42j has been fully advanced.The work-V piece will now become heated between the electrodes. When theoperator sees that the appropriate forging temperature has been reached,he depresses the push button H2, thus cutting off the heating currentand preventing the work from becoming heated further and at the sametime operating the solenoid |4| to release the latch |31 and permit thelever 8| to rise. The ram 42 will thereupon move to the left and drawthe vice I6 away from the vice |1, pulling the workpiece out to anextent which may be limited by the stop 46, or may proceed until it isdrawn apart and two pointed workpieces formed.

If desired instead of allowing the operator to vjudge the forgingtemperature, some form of temperature-responsive device may be locatedclose'to the workpiece between the vices I6, |1 and connected to thesolenoid |'4| so as to operate it automatically.

Thus stretch-forging, intermediate upsets, end upsets vand welds can allbe expeditiously and enlciently effected on this machine.

It will beunderstood that although a hand-fed mechanism has beendescribed for the vice |1,

it would be possible to employ any other form of feed, such as a lighthydraulic feed under hand control, in its place.

When tension forging operations are conducted with the described machineit is desirable to increase the hydraulic pressure so as to ensure asecure grip of the vices upon -the workpieces, without slipping. 1

I claim:

l. In a butt-welding machine, the combination.

spect to the support toward and into welding sure therebetween. feedingmeans for engaging' and applying heavy pressure to the workpiece carriedby the other of said supports to displace such workpiece with respect tothe support toward and into welding union with the other workpiece, andmeans operable on completion of movement of said firstrnamed support toa which is such as to permit said machine to be 5 used for both weldingand forging operations. v EMERIC GASPAR.

